Deep well pumping mechanism



3 Sheets-Sheet l C. C. CARLISLE DEEP WELL PUMP'ING MECHANISM Filed Sept.18, 1940 zvenor' Charles C.' .Carlisle By is Aiorn J' June 30, 1942.

752 ven Z'O?a 3 Sheets-Sheet 2 C. C. CARLISLE Filed Sept. 18, 1940 iw CDEEP WELL PUMPING MECHANISM d k y .nine 3o, 1942.

C. C. CARLISLE DEEP WELL .PUMP/ING MECHANISM Filed sep't. 18. 1940 5Sheets-Sheet 3 Mumwwli....1.1.2....UU.HHH......\.........,.......H...|.|.....\...

ssi.,iisi....i ii!! w//zl llllllllllllllll l Patented ,June 30, 1942UNITED VSTATES PATENT OFFICE DEEP WELL PUMPmG MEcnANIsM charles c.Carlisle, Independence, Enns; Applleenon Septemberm, 1940, serial No.357,249

14 claims. (criar-157) My present-invention relates to deep well pumpingmechanism of the type wherein the-pumping mechanism is contained withina tubular'casing that is insertable into i and readily renvable from thetubular Well casing of a deep well such as employed in pumping oil fromgreat depths.

The present invention is in the nature of an improvement on,`ormodication of the pumping mechanism disclosed *and more broadly claimedin my prior Patent 2,118,547, issued May 24, 1938,

and entitled Deep well uid motor. In a deep well pumping mechanism of:this character, a cylinder and piston pump and, cylinder and pistonfluid actuated motor, are located in the lower por;

In the accompanying drawings, which show the latest improved form oi.'the invention, like char- .acters indicate like parts throughout theseveral views.

Referring to the drawings: l Eig. 1 is an Y axial section with someparts broken 'away -showing .the improved fluid-actuatefd pumpingmechanism in its enclosing casing ,placed within the relatively iixeddeep well cas-v jf ing;

Fig. 2 is an axial section of those parts which .i'n Fig. 1 are betweenthe 'points marked aand b:

, Fig. an axial section through those parts .shown between .the'poiritsb and c on Fig'. 1.

tion of the long tubular pump casing and throughf-lli 4 is an axialsection of thse' parts shown a valve mechanisml and cooperating devicesalso betweenthehppints c an'dd, on Fig; 1;

located within the pump casing; .the piston of the motor-isre'ciprocated by fluid pressure produced at t the y upper `end or thefluid pressure string of tubingand at thetop vof the well; .and the pumppiston is connected to the motor piston so that the two pistons aregiven simultaneous and like reciprocating movements.z f, .Thearrangement of the valve mechanism is such thatthe fluid pumped downthrough the pressure string of tubing to reciprocate the above notedpistons will be commingled with` the fluid pumped upward under thereciprocating movements of the motor and pump pistons.l

The advantages of the mechanism involved in Y my prior patent over typesof deep well pumps" mechanically operated from the top of the wellthrough a long string of sucker rods is very fully discussed in my saidprior patent and these now known advantages need not here be repeated toany great length.

Obviously this type of pumpme'chanism may be used for pumping any or allkinds of fluids from great depths. ever, will be the pumping of oil andWater, and

depths; hence hereafter in this speciiication the mechanism will beassumed to be for the pumping ofv oil, and the term oil will be used ina broad and liberal sense.

Generally-stated,'the objects of the present invention aresimplification of constructionand v low cost of production; ysmoothnessand depend- The principal uses, howA 4o especially for the pumping ofoil 'from great" 50 stroke.

, ,Fig. gis. a transverse section taken on 'the line Fig. 6 is atransverse section4 taken on the line f" Figs'. '1, 8 and 9 are axialsections of those .parts. whlch.rin.Fig.-e1. -are vbetl'veen the pointsmarked aand c', certain'parts'being broken away gand some parts beingshown in full, the said views "26.51, B'n'and 9 showing the lmpvingparts of the .mechanism in different positions.

Advance statement of structure and operation. The pump illustrateda'nddescribed herein is adoubleacting pump of the cylinder and reciprocatingpiston type and is mechanically connected tothe piston of a cylinder andpiston reciprocating duid-actuated motor. When it is oil that is beingpumped,the motive uid will like- ',wise be'oil, and this motive fluidwill, by suitable means, be located at the top of the well. and bepumped down the Well to the motor through a central string of-tubing.This central string of tubing and its 'connected parts are locatedWithin a second string of'tubing of larger diameter which, in turn, isinserted within the tubular well casing.

'I'he pump piston reciprocates as a unit with 5 the motor piston, and ateach'stroke it draws into the pump cylinder, at one side of the piston,oil from the well and forces out of the pump cylinder Iat the other sideof the piston the oil that was drawn into the cylinder on the previousThe oil discharge from the pump is forced upward through an annularpassage between the two strings of tubing, where it meets the oilexhausted from the motor, and the mixture of the two is forced to thetop of the well,

through an annular passage surrounding the above mentioned centralstring of tubing through which the motive uid is supplied to thepump.

Before describing in detail the various parts ot the mechanism,attention is particularly called to Fig. 1, which on a small scaleindicates substantially the full length of the pumping mechanisminserted in the well casing. In this View, and in the views on a largerscale, the fixed outer or well casing is indicated at I I. The purrptubing, which will usually be a string of pipe sections, and which isextended within the well casing II, is indicated by the numeral I2, and,of course, extends to the top of the well and nearly to the bottom ofthe well. Within the pump tubing I2 is a string of tubes includingtubular sections I3, I4, I and I6, coupled together by tubular memberspresently to be described. The lower tube I6 extends to the bottom ofthe well and to the source of oil well' uid supply, while the lower endof the tube I2 is closed by a swedge nipple I1 connecting withihe lowertube I6, as shown in Figs. 1 and 4.

It will of course be noted that the well casing is of considerablelarger diameter than the pump tubing I2 so that the pump mechanism canbe freely inserted into or removed from the well casing. Also it will benoted that the tubular sections I3, I4, I5 and I6 are spaced from theenclosing tubing I2. The lower or iluid pick-up tube I6, at its upperend.. is extended through a tubular coupling I8, the expanded portion ofwhich is threaded into the lower end of tube I5 as best shown in Fig. 4.Within the upper end of tube I6 is a plug or head I9 that has ports 26normally closed against downwardmovement of fluid by an annular checkvalve 2| subject to gravity and springs 22, which latterare compressedbetween said check valve and a ilanged cap 23 secured on the head I9.The expanded portion of the coupling I8 has ports 24, andreversingacting ports 25.

The extreme upper portion of coupling I8 is connected by screw threads,or otherwise to the lower end of a pump cylinder 26 that is locatedaxially within and extends from the tube I5. The ports 24 connect theupper portion of intake tube I6 to the space between the pump cylinder26 and surrounding tube I5; while the ports 25 connect the lower portionof the pump cylinder to the space between the tubing I2 and tube I6.Ports 25 are normally closed against upward ow of fluid by an annularcheck valve 21 that is subject to springs 28 seated against a collar 29secured on the coupling I8. An annular collar 39, by threaded engagementor otherwise, is secured to the upper end of cylinder 26 and to theupper end of tube I5, see particularly Fig. 3. This collar 33 has portsor iluid passages 3l. An annular collar 32, by threaded engagement orotherwise, is secured on the threaded upper end of collar 39 and has athickened upper annular portion, which, as shown, is screw threaded onthe reduced end of a coupling head 33, which in turn is screw threadedinto the lower end of tube I4. Collar 32 has ports, or iluid passages34, normally closed against the downward flow of fluid by an annularcheck valve 35, subject to gravity and to springs 36, which latter reactagainst annular shoulders of the head 33. The ports 3i in thickenedportion of collar 39 are normally closed against the downward ow of uidby an annular check valve 31 subject to gravity and springs 33,

which latter react against the annular shoulder of collar 32. The motorcylinder 39, also best shown in Fig. 3, is spaced from the tube I4 andis telescoped with a tight Joint around a reduced portion of thecoupling head 33. The upper end of the motor cylinder 39, as best shownin Fig. 2, is threaded onto an annular valve housing 40, the reducedportion of which is threaded into coupling collar 4I. Collar 4I is shownas threaded into tubular casing 42, which in turn is screw threaded ontothe lower end of tube I3. The expanded lower portion of valve housing 40is also screw threaded into the upper end of tube' I4. A

Tube I3, it will be remembered, extends to the top of the w ell and isconnected to a source of Huid supply under pressure, which in an oilwell vwill be oil, but in case of a. water pumping mechanism will bewater. The annular valve housing 40 is provided with ports or uidpassages 43 and 44. The ports 43 are closed against downward ow of fluidby an annular check valve 45 subject to springs 46 that react .againstthe annular shoulder of coupling sleeve 4I. Working in the pump cylinder26 is a pump piston 41 and working in the motor cylinder 39 is a motorpiston 48. The said pump and motor pistons are connected forsimultaneous and like movements 'by a piston rod 49, which as shownworks through stuilingv boxes 56 applied to the coupling head 33. Alsoin the particular structure illustrated, the lower end oi' piston rod 49is connected to pump piston 41 by a threaded coupling cap 5I and theupper -and have an upward nare or increased cross section, which assistsin producing a cushioning action of the downward movement of the twopistons. The annular valve house or casing 46 has a tubular skirt orportion 40a formed with ports 40h, see Fig. 2.

The valve housing further includes a tubular body 54 which is detachablysecured to the skirt 40a, preferably by threaded engagement, and thelower end of which is closed by a detachable head 55 having an axialstuiling box 56.

Working within the valve housing 40 and within the skirt 40a is areversing valve 51 having piston-like valve heads 51a and 51h, and has adepending skirt 58 formed with ports 59 and 69. The skirt 58 has asupplemental tubular outer portion 6I secured thereto by welded orthreaded engagement and extended below saidv skirt. This supplementalouter portion 6I has a close sliding ilt with the tubular body` 54.Secured to the lower portion of supplemental section 6I is a tubularsection 82 that is formed with ports 63. The lower end of 62 is closedexcept for a stuffing box 64. An inverted cap 65 is shown as applied tothe lower end of said member 62. The lower piston-like head 51h isformed with uid passages or ports'66 that lead from the space betweenthe heads 51a and 51h down into the annular space that leads to port 66.

Working within the cylinder formed by the skirt 58 of reversing valve 51and the tubular section 62, which latter has the ports 63, is a pilotvalve 61, which has an'upper piston-like head 61a, and a lowerpiston-like head 61b. Above its upper head 61a, tubular pilot valve 61is provided with ports 63.

Extended axially upward from the pilot valve 61 and through the valvehousing or casing 46 is a tubular stem 69. Secured to the upper end ofstem 6l is a tubular stem extension member or portion 18 to which.`by acoupling sleeve 1I. is

`attached a tubular plunger guide or stem extenoperation is renderedmore certain and all points of dead center or stopping positions, wherethe member 18 forms an element of the pilot valve 81. Toggle actinglinks 18, which are shown in 1 duplicate, see Figs. 2 and 5, areat'thelr inner ends pivotally connected to the stem element 18.Connecting rods 18 are pivoted to the outer ends valve 51. Coil springs11 or the like applied to the rods 18 tend to hold the toggles 15buckled.

Attention is now directed particularly to Figs. 2 and 3. Extendedaxially through the above mounted members 14, 12, 18 and 89, pilot valve81, and downward into the'a'xial cavity of the motor piston 48, .is apilot-valve actuating rod 18, which has limited vertical movements withrespect to all the members through whichit has passed. Within the cavityof the motor piston 48 the rod 18 has a head 18.

In the particularstructure illustrated, piston 48 has a rigidly securedbut detachable upper end cap. 88 with vent passages 8l. Under extremedownward movements, cap 88 will engage the head 19 of rod 18, but underextreme upward movements of said piston cap 80 will engage a collar 82that is rigidly but adlustably secured on said rod 18 above said cap,Within the tubular element 12 ofthe string of pilot valve stem formingelements, rod 18 has a plunger or collar 18a. Within the said tubularelement 12, below` collar 18a is a coiled spring 83 that reacts againstthe upper end of element 18; and in the upper portion of said member 12above said collar 18a is a coiled spring 84 that reacts against theadjustable screw-acting element 14. The tension of the opposing springs83 and 84 will be so adjustedthat they will tend to hold the pilot valveactuating rod 18 in the position shown in Fig. 3. It will be noted, byreference particularly to Fig. 2, that the cavity of the-element 82below the pilot valve 81 and the bottom forming surface of the head orplug 55, which is belowthe reversing valve carried velement 85, areannularly dished so that sediment or solid material will be ilushed andcarried out with the flowing stream of oil or fluid, Also within thesaid annularly dished chamber a limitedv amount of ymercury may b eplaced if necessary to keep sediment `or solid particles from settlingwithin said chamber or pocket, thereby facilitating the flushing out ofsuch sediment at the intermitting flow of fluid therethrough. Likewise,the pocket at the base of pilot valve 81, below 61h, may be suppliedwith mercury for the same purpose as above stated, it necessary. i

In the structure of my prior patent there was provided a fluid motor tooperate the main slide valve; 4but in my present improved pump, the mainslide valve, which in itself is a reversing valve, is controlleddirectly by a pilot valve which controls alteration of pressures on thedlierential cross-sectional areas of said main slide valve or reversingvalve, the main elementsof which latter are indicated by the numerals51, 8| and 85. Otherwise stated, in the prior patent, pressure wasalternated on opposite sides of the auxiliary or so-called fluid motorwhich, in turn, operated the main slide valve, but in my present device,the auxiliary motor is eliminated and the main slide valve is operatedby alternating pressure on opposite sides thereof. These differences ofthe links 18 and to the upper end of reversing device will not beself-starting, are eliminated.

Operation In the position of the parts shown in Fig. 2, I'

oil under pressure is being forced downward through tube I8, casing 42,cavity of reversing valve housing 48, its ports 44, the annular spacebetween tubes 38-I4, and ports 53 into interior of cylinder 39; and thepressure of oil will then force motor piston .48 to move upward carryingwithit pump piston 41. The simultaneous upward movements of the motorand pump pistons cause oil to be drawn upward through and into the lowerportion of pump cylinder 26, through the tubing I8 and ports 20 and pastcheck valve 2 I, which freely rises to permit such flow. At this time,oil cannot ilow upward through ports 24 partly because of the partialvacuum produced therein at this time and the pressure of oil that isdelivered into the upper portion of the pump cylinder under previousstrokes.

rUnder this first noted upward stroke the oil previously delivered into,the upper portion of the pump cylinder 28 will be forced upward throughports 84 lifting check valve 35 and from thence upward through theannular space between the tubing I2 and I4 and from thence to thedelivery point at the top of the well. Also under this first notedupward movement ofthe motor and pump pistons, the oil contained in motorcylinder 39 above piston 48 will be forced upward from the upper portionof the motor cylinder 39 through the annular space between said cylinder39 and housing 54, and thence through ports 40h and 43 lifting checkvalve 45, and from thence on upward through the annular space between 42and I2, and I2 and I3 to the top of the well.

When under the upward movement of the two pistons, motor piston 48engages collar 82 on the pilot rod 18, said rod will be moved upward byand with said motor piston, thereby pressing upward collar 18a of saidrod 18against the action of the upper spring 84, see particularly Fig.2. When spring 84 has-been compressed to a certain predetermined extentit will cause upward snap movement of the elements 12, 10, 89, `andpilot valve'il. It will beremembered that the pivotal connection betweenthe toggle links 15 is made directly on the stem extension 10. Hence,when the pilot actuating elements just noted are moved to -apredetermined extent so that when this pivotal connection is moved pastthe dead center, the

` shown in Fig. 2 into the position shown in Fig. '1.

said toggle will, under tension of spring 11, snap from the positionshown in Fig. 2 into the reversed position in Fig. '1. 'I'his snappingmovement of the toggle from one side to the other of the dead centerdoes not cause any movement of yreversing valve 51 in respect to theannular valve housing -40 in which it is mounted. However, the abovenoted upward movement of the pilot valve actuating stem made up of theseveral elements noted, moves the pilot valve 61 from the position Atthis time the motor and pump pistons have substantially completed theupward movements. In the position of the valve mechanism incorporatingparts shown in Fig. '1, the oil under pressure is forced downward fromthe tubular .casing 42 through the annular valve housing 40, downwardlthrough the center of the tubular in structure lare highly important notonly be- I cause the lstructure is simplified, but because the throughtubular housing 42 through the interior of the reversing valve 51through ports 59-48b, through annular space between motor cylinder 89and valve housing 54 to the top of motor cylinder 48, and this pressurethereby forces the motor piston 48 4and the pump piston 41 downward.

Under downward movement of the two pistons just noted, the oil frombelow the motor piston 49 will be discharged through ports 53 into theannular space between the motor cylinder 39 and tube I4, and from thenceupward through ports 44 and 43, check valve 45 and into the annularspace between tubular casing 42 and I2 to the top of the well.

At this time, and under the same downward piston movements, the oilpreviously. drawn into the pump cylinder 25 will be discharged downwardthrough ports 25 and check valve 21 into the annular space between thetubing I2 and I5.

, It will now be noted that the oil pumped down from the top of the wellto operate the motor piston is returned to the top of the well with theoil pumped from the bottom of the well.

When the motor and pump pistons closely approach the limit of theirdownward movements, the head 19 of pilot rod 18 will be engaged by thecap 80 on the top of the motor piston 48, and said rod 18 will be forceddownward against the action of lower spring 89, thereby causing thepilot valve and its multisection operating stem,

Further comments and more detailed description of certain operationsPorts 53 are axially elongated so that when the power piston begins tocover them their effective areas are progressively restricted untilthepiston reaches the limit oi its downward movement. The power pistonis further cushioned by the reversing of the pressure fluid to theopposite end of the piston Just before it reaches the limit of itsstroke in either direction, thereby further cushioning, if not entirelyarresting and reversing its motion.

As the links are thus thrust apart, the thrusting force of compressedspring 84 will increase the effective lateral thrust on links 15 as theangle between them approaches 180 degrees. Since this effective thrustincreases faster than the resisting force of the springs 11, themovement results in a quick snap action, producing a quick upwardmovement of thev elements 12, 10, 89 and the pilot valve 61. -It will beremembered that the pivotal connections between the toggle links 15 aremade directly on the stem extension 10. Hence when the pilot actuatingelements including the elements 10 and 15, to snap back to the positionsfirst noted and shown in Fig. 9. This takes place, prior to movement ofthe reversing valve, and the pilot valve will be set in respect thereto,so that the flow of the oil will be as follows: the oil under pressureflowing downward through the tubular reversing valve will pass throughports 58, and the interior of the pilot valve 51, to the bottom of thecylindrical chamber in which said pilot valve is mounted. The oilpressure then will act on the top of reversing valve 51 and on thebottom of the cylindrical surface in which the pilot valve. is mountedand which cylindrical surface, it will be remembered, .is formed in theextension 82 of said reversing valve; and this pressure will move thereversing valve from the position shown in Fig. 9 to the position shownin Fig. 2.

At the time Just noted, when the reversing valve is moved back into theposition shown in Fig. 2, the pilot valve will, -through the connections18-15, be caused to move with the reversing valve without changing therelative `position in respect thereto. When the reversing valve andpilot valve are lsimultaneously moved downward and back to the positionshown in Fig. 2, the flow of the oil caged in the lower end of the valvehousing 54 will be forced upward through ports 83, 88, passage 88, ports4l, and past check valve 4l, thereby entering the annular space betweenpump casing I2 and tube casing 42 where it commingles with the oilpumped from the bottom of the well in a manner alreadyv described.

just noted are moved through toggle action, this pivotal connection ismoved, in snap action, by the compressed spring 84, through and pastdead center of the toggles and from which latter position onward by theassistance of contracting springs 11, from the position shown in Fig. 2,into the reverse position in Fig. 7.

It will be noted that the parts of reversing valve 51 are so designedand constructed that 51a, 51h, and 5I each has circular cross-sectionalareas so proportioned that they have proper differential areas exposedto the operating pressure. When pilot valve 51 is moved from one extreme position to the other, thus alternating opening and closing ports63, the resulting fluid pressure on the differential areas of the main Ior reversing valve 51 will cause alternations of the latter.

It will be noted that the fluid pressure in the chamber around the valve51 between 51a and 51h and through port 59 is constantly the static ordischarge pressure as in the annular space between tubing sections I2and I4 and that the pressure within the reversing changing valve 51, ontop of the upper end of 51a and .in the valve chamber below pilot valve51 is constantly equal to that of the pressure fluid within tubing I2,while that within the chamber below cap 55 within the chamberencompassing it varies between that of the pressure fluid within tubingI2, and the discharge pressure within the annulai` space between tubingsI2 and I4, depending onthe position of' pilot valve end 51h, that is,whether it is above or below port 83.

The cross-sectional areas of valve 51 and its associated parts are soproportioned that such areas multiplied by the pressure in contact withthem are such that the valve 51 is forced to move within its restrictedlimits as the pilot valve 81 uncovers or blocks the passage of pressurefluid through port 83 and thereby changes the fluid pressure within thepower cylinder 98,'

alternately on the ends of power-piston 48, all

y 2,937,779 l apparire-ener ofifinemeibrcyimder with s high pressureiluid supply and with a low pressure exhaust, an extension on said slidevalve cooperating withv the valve casing to form an alternate high andlow pressure chamber, a pilot valve slidable in` said extension of thereversing valve to alternately' connect the highpressure iluid supplywith said chamber and with said low pressure exhaust toeilectjmovementoithe reversing valve inthe casing. and a reciprocating `member havinglost motion connection with the motr piston and having connection withsaid pilot valve to elect shifting of the pilot valve in selectivepositions of the motor piston. i 2. In an apparatus of the characterdescribed, a motor cylinder, a motor piston in said cylinder, areversing valve casing connected with the motor cylinder, a reversingvalve slidable in the casing and adapted to alternately connect theopposite ends .of the motor cylinder with a high pressure iiuid supplyand with a low pressure exhaust, an extension on said slide valvecooperating with the valve casing to form an alternate high and lowpressure chamber, a pilot valve slidable in. said extension toalternately connect the high pressure iluid supply with said pressurechamber and with said low pressure exhaust to effect movement of thereversing valve in the casing, a reciprocating member having lost motionconnection withthe motor piston and having connection with said pilotvalve for shifting of the pilot valve in said reversing valve atselected positions ofv the motor piston to effect alternate admissionand exhaust of the high .pressure lluid to and from said chamber formoving the reversing valve, and `connecting means between the pilotvalve and the reversing valve to maintain relative position of saidvalves during movement of the reversing valve.

3. In an apparatus of the character described, a motor cylinder, a motorpiston in said cylinder, a reversing valve casing connected with themotor cylinder, a reversing valve slidable in the casing and adapted toalternately connect the opposite ends of the motor cylinder with a highpressure iiuid supply and with a low pressure exhaust, an extension onsaid slide valve cooperating with the valve casing to form an `alternatehigh and low pressure chamber, a pilot valve slidable in said extension'to alternately connect the high pressure iiuid supply with said high andlow pressure chamber and with said low pressure exhaust to eifectmovement of the reversing valve in the casing, a reciprocating memberhaving lost motion connection with the motor piston and having yieldingconnection with said pilot valve to effect shifting of the pilot valvein selective positions of the motor piston to effeet alternate admissionand exhaust of the high pressure'. iluid to and fromsaid chamber for-moving the reversing valve in said cylinder, and

a snap acting toggle connection between the pilot valve and thereversing valve, said toggle con-l nection being adapted to maintainrelative position of said valves during movement of the reversing valve.

4. In an apparatus ofv the character described, a motor cylinder, amotor piston in the cylinder, a reversing valve casing having spacedports connected with the motor cylinder on opposite sides of the motorpiston and having an exhaust port, a reversing valve slidable in thecasing and adapted to alternately connect said spaced ports with a highpressure iluid supply for effecting reciprocation of said motor piston,

the valve casing to form an alternate high and low pressure chamber andhaving a port connected with the exhaust port and a port connected withsaid chamber, a pilot valve slidable within said extension toalternately connect the port which iii-connected with said chamber withthe port which is connected with the low pressure exhaustiand with thehigh pressure fluid supplysand a reciprocatory member having lost motionconnection with the motor piston and a connection with the pilot valveto eect shifting of the pilot valve in said extension.

5.l In an apparatus o! the character described, a motor cylinder, amotor piston in the cylinder, a reversing valve easing having spacedports con,-y nected with the motor cylinder on opposite sides of themotor piston and having an exhaust port, a reversing valve slidable inthe casing and adapted to alternately connect said spaced ports with ahigh pressure iluid supply for eilecting reciprocation of said motorpiston, an extension on said slide valve cooperating with the valvecasing to form an alternate high and low pressure chamber and having aport connected with the4 exhaust port and a port connected with saidchamber, a pilot valve slidable within said extension to alternatelyconnect the port which is connected with said chamber with the portwhich is connected with the low pressure exhaust and with the highpressure fluid supply, a reciprocatory member having lost motionconnection with the motor piston and a yieldable connection with thepilot valve to effect shifting of the pilot .alve in said extension, anda snap acting connection between the pilot and reversing valves.

6. In an apparatus of the character described, a motor cylinder, a motorpiston in the cylinder, a reversing valve casing connected with themotor cylinder, a tubular reversing valve adapted for reciprocation inthe reversing valve casing for controlling inlet and discharge of highpressure fluid to the motor cylinder for reciprocating said motorpiston, an extension on the reciprocable valve and cooperating with thereversing valve casing to form an alternate high and low pressurechamber, a tubular pilot valve reciprocable in said extension foralternately admitting a high pressure iluid to said chamber and toexhaust said pressure for eiecting reciprocation of the reversing valve,a tubular stem connected with the pilot valve and extending through thereversing valve, a rod extending through said stem and having lostmotion connection with the'motor piston, a collar on said rod, a springhousing connected with the pilot valve stem, coil springs sleeved overthe rod on the respective sides of the collar and enclosed in saidhousing, toggle links having connection with theV pilot valve stem,links connecting the toggle links with said reversing valve, and springsnormally retaining the toggle links in collapsed position.

7. In an apparatus of the character described, a motor cylinder, a motorpiston in the cylinder, a reversing valve casing connected with themotor cylinder, a tubular reversing valve adapted for reciprocation inthe reversing valve casing for controlling inlet and discharge of highpressure fluid to the motor cylinder for reciprocating said motorpiston, an extension on the recprocable valve and cooperating with thereversing valve casing to form an alternate high and lowpressurechamber, a tubular pilot valve reciprocable in said extensionfor alternately admitting a high pressure uid to said chamber and toexhaust.

. an extension on said slide valve cooperatinglwith the pilot valve andextending through thereversing'valve,arodextendingthroughsaidstem,stopsonsaidrod,meansonthemotor for engaging lsaid stops to shift therod, on saidirod, aspring housing connected valve stein,v coil springssleeved respectivesidesofthecollar valve, and springs normally retainingthe toggle links in collapsed position.

8. In an apparatus ot the character described, a motor cylinder. a motorpiston in said cylinder, a reversing valve casing connected withthemotor cylinder, a reversing valve slidable in the casing and adapted toalternately connect the opposite ends of the motor cylinder with a highpressure iluid supply and with a low pressure exhaust, an extension onsaid slide valve cooperating with the valve casing to form an alternatehigh and low pressure chamber andhaving a greater eifective pressurearea than the eil'ective area of said reversing valve, a pilot valveslidable in said extension to alternately connect the high pressurefluid supply with said high and low pressure chamber and with said lowpressure exhaust to eilect movement of the reversing valve in thecasing, and a reciprocating member having lost motion connection withthe motor piston and having connection with said pilot valve to eectshitting of the pilot valve in selective positions of the motor piston.

9. In an apparatus o! the character described, a motor'cylinder", amotor piston in the cylinder,

a reversing valve casing havingv spaced ports connected with the motorcylinder on opposite sides of the motor piston and'having an exhaustport, a. reversing valve having piston-like heads of differentialdiameters movable over the spaced ports alternately admitting a highpressure fluid to the respective ends of the motor cylinder and toexhaust said uuid ioreil'ecting reciprocation oi.' said motor piston, anextension on said valve having a diiierential'diameter than thepistonlike heads and cooperating with the valve casing to form analternate high and low pressure chamber and having a port connected withthe exhaust port and a port connected with said chamber, a pilot valveslidable within said extension to alternately connect the port which isconnected with said chamber with the port which is connected with thelow pressure exhaust and with the high pressure fluid supply, areciprocatory member having lost motion connection with the motor pistonand a connection with the pilot valve to eiiect shifting of the pilotvalve in said extension, and a snap acting toggle connecting the pilotand reversing valves.

10. In an apparatus of the character described, a motor cylinder, amotor piston in the cylinder,

a reversing valve casing connected with the mo tor cylinder. a tubularreversing valve adapted for'reciprocation in the reversing valve casingfor controlling inlet and discharge of high pressure lluid`to the motorcylinder for reciprocating said motor piston, an extension on thereciprocable valve and cooperating with the reversing valve casing toform an alternate high and low la'tubular stem connected with.

.ahighpressureiluidtosaidchamberandtoex' pressure chamber, a tubularpilot valve reciprocable in said extension for alternatelyadmittinghaust said pressure tor electing reciproeation oi.' thereversing valve, a tubularlstem'connected with the pilot valve andextending through the reversing valve, a rod extending through saidstem,spacedstopsonsaidrod,meansonthemotorvitonforengssingsaidstopstoshiittherod,acollaronsaidrod,aspringhousingcon nected with the pilot valve stem.coil springs sleeved over the rod on the respective sid of the collarand enclosed in said spring housing, toggle links having connection withthe pilot valve stem, links connecting the toggle links with saidreciprocable valve, springs normally retaining the toggle links incollapsed position, and packing means sealing the rod relatively to saidextension and the reversing valve casing.

11. In an apparatus of the character described, a reversing valve casinghaving an annularly 4dished pocket in an end thereof, a reversing valveslidable in the easing, an extension on said valve having an endcooperating with said pocket to form annalternate high and low pressurechamber, and a pilot valve slidable in said extension to alternatelyconnect a high pressure fluid supply with said pressure chamber to eiectshifting of the reversing valve.

12. y,In an apparatus of the character described, a reversing valvecasing having an annularly dished pocket in an end thereof, a reversingvalve slidable in the casing, an extension on said valve having an endcooperating with said pocket to form an alternate high and low pressurechamber and having an interior pilot valve chamber slidable in thecasing, an extension on said valve having an end cooperating with saidpocket to form an alternate high and low pressure chamber, a pilot valveslidable in said extension-to alternately connect a high pressure uidsupply with said pressure chamber, and a body of mercury contained insaid pocket.

14. In an apparatus of the character described, a reversing valve casinghaving an annlarly dished pocket in an end thereof, a reversing valveslidable in the casing, an extension on said valve having an endcooperating with said pocket to form -an alternate high and low pressurechamber and havingan interior pilot valve chamber provided with asimilarly shaped pocket, a pilot valve slidable in the chamber of saidextension to alternately connect a high pressure iluid supply with saidpressure chamber, said high pressure iluid being admitted to said pilotvalve chamber coaxially of the pilot valve for eilecting a flushingaction relatively in said pocket therein, and bodiesofmercury containedin said pockets.

CHARLES C. CARLISLE.

